Contents

Drafty Slony-I Site

Please note that this site is presently under heavy
construction .

It will soon be able to be actively used for Slony-I
CVS, downloads, and mailing lists; it's not quite
ready yet, so for now, you likely still want to look to the
gBorg Slony-I project for the time being.

There will be announcements on the gBorg-based mailing
lists indicating the migration when all is ready...

Slony-I

Slony-I is a "master to multiple slaves"
replication system with cascading and failover.

The big picture for the development of Slony-I
is a master-slave system that includes all features and
capabilities needed to replicate large databases to a
reasonably limited number of slave systems.

Slony-I is a system for data centers and backup sites,
where the normal mode of operation is that all nodes are
available.

A fairly extensive "admin guide" comprising material
in the CVS tree may be found here
There is also a local copy here

A patch for both version 1.1 "STABLE" and CVS HEAD has
been committed to CVS; look at both CVS HEAD as well as
REL_1_1_STABLE. It is in the 1.1.5 release
candidate described above.

Upgrading Slony-I

Beginning with version 1.0.5 the slon replication
engine refuses to work against any database that does not
have the stored procedures for the same version loaded or
where the shared object containing the C language support
functions and the log trigger does not match the version
number.

This means that the Slony installation on all nodes in
a cluster must be upgraded at once.

The proper upgrade procedure is this:

Stop the slon replication engine on all nodes.

Install the new Slony version on all nodes.

Execute a slonik script containing the command

update functions (id = );

for every node in the cluster.

Start all slon replication engines.

Libpq requirements

The multithreaded replication engine requires the
libpq client library to be compiled with
--enable-thread-safety on certain operating systems.
Known are thus far Solaris and AIX. Other operating
systems are known to not require this (Linux-X86,
FreeBSD-X86, FreeBSD-Alpha, OpenBSD-Sparc64 and OSX).
The configuration script is broken with respect to
the --enable-thread-safety switch for Solaris. Please
apply this patch, configure and recompile libpq:
threadsafe-libpq-742.diff.gz.

RPMs

RPM files for some versions of Red Hat Linux are
available here ,
including SRPM (Source RPM) files that may be helpful
if you wish to generate RPM files for distributions
not yet supported.